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  2. Astronomical coordinate systems - Wikipedia

    en.wikipedia.org/wiki/Astronomical_coordinate...

    Coordinate systems in astronomy can specify an object's relative position in three-dimensional space or plot merely by its direction on a celestial sphere, if the object's distance is unknown or trivial. Spherical coordinates, projected on the celestial sphere, are analogous to the geographic coordinate system used on the surface of Earth.

  3. List of stars for navigation - Wikipedia

    en.wikipedia.org/wiki/List_of_stars_for_navigation

    The other two cover the equatorial region of the celestial sphere, from the declination of 30° south to 30° north. The two equatorial charts are mercator projections, one for the eastern hemisphere of the celestial sphere and one for the western hemisphere. Note that unlike familiar maps, east is shown to the left and west is shown to the right.

  4. Star chart - Wikipedia

    en.wikipedia.org/wiki/Star_chart

    A celestial map by the Dutch cartographer Frederik de Wit, 1670. A star chart is a celestial map of the night sky with astronomical objects laid out on a grid system. They are used to identify and locate constellations, stars, nebulae, galaxies, and planets. [1] They have been used for human navigation since time immemorial. [2]

  5. Equatorial coordinate system - Wikipedia

    en.wikipedia.org/wiki/Equatorial_coordinate_system

    Model of the equatorial coordinate system. Declination (vertical arcs, degrees) and hour angle (horizontal arcs, hours) is shown. For hour angle, right ascension (horizontal arcs, degrees) can be used as an alternative. The equatorial coordinate system is a celestial coordinate system widely used to specify the positions of celestial objects.

  6. Celestial navigation - Wikipedia

    en.wikipedia.org/wiki/Celestial_navigation

    Practical celestial navigation usually requires a marine chronometer to measure time, a sextant to measure the angles, an almanac [2] giving schedules of the coordinates of celestial objects, a set of sight reduction tables to help perform the height and azimuth computations, and a chart of the region. [3]

  7. List of nearest stars - Wikipedia

    en.wikipedia.org/wiki/List_of_nearest_stars

    Animated 3D map of the nearest stars, centered on the Sun. 3D red green glasses are recommended to view this image correctly. A radar map of the distances ( ) and positions ( ) of all known stellar bodies or systems within 9 light years (ly) (for within 12 ly see this map).

  8. Ecliptic coordinate system - Wikipedia

    en.wikipedia.org/wiki/Ecliptic_coordinate_system

    In astronomy, the ecliptic coordinate system is a celestial coordinate system commonly used for representing the apparent positions, orbits, and pole orientations [1] of Solar System objects. Because most planets (except Mercury ) and many small Solar System bodies have orbits with only slight inclinations to the ecliptic , using it as the ...

  9. Nautical almanac - Wikipedia

    en.wikipedia.org/wiki/Nautical_almanac

    The "Air Almanac" of the United States and Great Britain tabulates celestial coordinates for 10-minute intervals for use in aerial navigation. The Sokkia Corporation's annual "Celestial Observation Handbook and Ephemeris" tabulated daily celestial coordinates (to a tenth of an arcsecond) for the Sun and nine stars; it was last published for 2008.